Cardiology Department, Royal Free London NHS Foundation Trust, Pond Street, London, NW3 2QG, UK.
Royal Brompton Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK.
J Nucl Cardiol. 2023 Aug;30(4):1497-1503. doi: 10.1007/s12350-023-03243-1. Epub 2023 Mar 17.
Cardiac AL amyloidosis is a medical emergency causing rapid deterioration of cardiac function; however, it remains to be a diagnostic challenge especially when presenting with unusual symptoms and clinical findings. We present case of a 44-year-old patient with typical angina, persistently elevated troponin and normal epicardial coronary arteries. He was initially treated for myocarditis due to chest pain with troponin rise. However, CMR finding of subendocardial enhancement, increased native T1 values as well as extensive diffuse FDG uptake on PET-CT also suggested inflammatory cardiac conditions. Rapid decline in LV function and clinical deterioration led to further investigations including serum free light chains and bone marrow biopsy which confirmed systemic AL amyloidosis. Although the pathophysiology of unusual FDG PET-CT findings remains unknown, marked myocardial FDG uptake might have been caused by various features that were associated with AL amyloidosis including myocardial cell toxicity/inflammation or microvascular dysfunction. Awareness of these features specific to AL amyloidosis among physicians and description of associated cardiac FDG uptake findings has a potential to aid early diagnosis.
心脏 AL 淀粉样变是一种医学急症，可导致心脏功能迅速恶化；然而，它仍然是一个诊断挑战，特别是当出现不寻常的症状和临床发现时。我们报告了一例 44 岁患者，其表现为典型心绞痛、肌钙蛋白持续升高和正常心外膜冠状动脉。由于胸痛伴肌钙蛋白升高，他最初被诊断为心肌炎。然而，CMR 发现心内膜下增强、原生 T1 值增加以及 PET-CT 上广泛弥漫性 FDG 摄取也提示存在炎症性心脏疾病。左心室功能的迅速下降和临床恶化导致进一步的检查，包括血清游离轻链和骨髓活检，证实了全身性 AL 淀粉样变性。尽管异常 FDG PET-CT 发现的病理生理学仍不清楚，但明显的心肌 FDG 摄取可能是由与 AL 淀粉样变性相关的各种特征引起的，包括心肌细胞毒性/炎症或微血管功能障碍。医生对 AL 淀粉样变性特有的这些特征的认识以及对相关心脏 FDG 摄取发现的描述，有可能有助于早期诊断。
